1. Field of the Invention
The present invention relates to a built-in type antenna for use within inside of an equipment, and a communication equipment incorporating the antenna.
2. Background Art
Portable telephone units and the like communication equipment are penetrating rapidly among our daily life. There are varieties of antennas available for incorporation in such equipment. Among the antennas, the recent preference is on a built-in type ones which are used incorporated in the inside of equipment cabinet.
A conventional built-in type antenna is described referring to FIG. 7 through FIG. 9.
FIG. 7 is a perspective view of communication equipment having a conventional built-in type antenna. FIG. 8 is a cross sectional view used to describe the key part, or a state how the antenna is mounted on a wiring board.
Referring to FIG. 7, a cabinet 101 of approximately rectangular parallelepiped shape with hollowed inside has on the front operation face a receiver portion 102, a display portion 103, an operating key portion 104 and a transmitting portion 105, in the order from the above.
Functional parts and the electronic components needed to operate the above-described receiver portion 102 through transmitting portion 105 are mounted on a wiring board 106 (see FIG. 8), which is supported and fixed in the inside of cabinet 101 at a certain specific position.
Microcomputer and the like control components for controlling the above parts and electronic components are mounted likewise on the wiring board 106. These parts and components exchange information among each other in order to put receiver portion 102, display portion 103, operating key potion 104 and transmitting portion 105 into operation.
A built-in type antenna 107 which transmits and receives radio waves (hereinafter referred to as built-in antenna 107) is also attached on wiring board 106, as shown in FIG. 8. The built-in antenna 107 is incorporated within cabinet 101.
FIG. 9 shows a perspective view of the built-in antenna 107. It is formed of a resin base body 108 having an approximate parallelepiped shape and a conductive metal sheet 109 functioning as the antenna element fixed on the upper surface. Shapes of resin base body 108 and conductive metal sheet 109 have been determined so that they are in conformity with a certain specific frequency region.
Built-in antenna 107 is attached and fixed to a certain predetermined location by inserting an elastic claw 108A, which is extending downward from the bottom of base body 108, through a cut 106A of wiring board 106 and hooking it on the reverse surface of wiring board 106.
Conductive metal sheet 109 in the above built-in antenna 107 has extensions to form a supply terminal 109A and a ground terminal 109B, respectively. Each of supply terminal 109A and ground terminal 109B is creeping down from the upper surface along the side wall surface of base body 108 with a certain specific width. The end parts of these terminals are bent to the form of a letter “L”, at the bottom level of base body 108.
As described in the above, the elastic arms extending from conductive metal sheet 109, or supply terminal 109A and ground terminal 109B, make at the bottom surface of L-bent sheet an elastic contact with wiring patterns 106B and 106C, respectively, provided on wiring board 106, in a state where built-in antenna 107 is mounted on wiring board 106 (see FIG. 8).
Built-in antenna 107 receives and outputs information via these wiring patterns 106B, 106C, supply terminal 109A and ground terminal 109B; and is controlled by the above-described control components which are connected by way of wiring patterns 106B, 106C. And the control components put other parts and electronic components into operating stage in accordance with the input/output information.
Description on a state how these control components control other components, and how the other components are functioning, are eliminated here.
A conventional built-in antenna 107 has the above-described structure, and mounted in the way as described above.
In the above-configured conventional built-in antenna 107, however, the supply terminal 109A and the ground terminal 109B making elastic contact on the wiring patterns 106B, 106C of wiring board 106 have a shape of a long elastic arm, made of an elastic metal sheet extended for a long distance along the side wall surface of base body 108. Therefore, it is difficult to keep the positioning accuracy under control. A resultant problem is that a wiring board 106 has to provide sufficient margin areas for the respective wiring patterns 106B, 106C.